What in the world is DNS?

Presented in every day terms, imagine a domain name, such as spestechnologies.com, as a household. That household has an address that is publicly known. The post office routes grocery store coupons to it, couriers bring packages, visitors come to hang out and so on. These visitors, depending on who they are and who they come to see, will spend time in different rooms of the house. All visitors access the house via the same front door. From there, they use other internal doorways inside the house. DNS is the actual doorway into the rooms whereas the rooms contain the data. The emails, pictures, documents and more.

If a domain name is a home, a DNS server is an address book

At a very high level, DNS, short for “Domain Name System”, is the Internet’s address book. It keeps a record of each address – where each household is located. But in the Internet’s address book, the addresses are stored a bit differently than you might expect. They’re stored as strings of numbers, not as the words we’d normally recognize. This is because computers are binary machines, meaning, they only understand 0s and 1s. And so, developers have to write code that tells the computer exactly what to do in a way it can understand it via these 0s and 1s. All those kitten pictures? There’s a combination of 0s and 1s that deliver and make them appear on screens everywhere.

To help deliver these kitten pictures, computers communicate over public and private networks, wired or wireless, via IP addresses. DNS was invented as the record keeping and translation service so that humans didn’t need to memorize a string of numbers, such as 216.92.12.51, for every single computer or server they wish to send or receive data from. Every device connected to a network has a unique IP address. It would be the equivalent of having to memorize GPS coordinates for every physical location a person wants to visit or send mail to. Can you imagine sending letters to coordinates? What a nightmare that would be!

How the address book is used

When a user types “spestechnologies.com” into their browser, the computer sends a request to one of these DNS servers (generally assigned by their Internet provider) to ask what IP address it should go to. Some additional magic happens and the website is loaded into the browser window. Internet providers such as ATT and Verizon, website hosts such as GoDaddy and large corporations such as Apple and Microsoft run public DNS master (root) servers (think of it as a library of address books) that communicate to other root-level DNS servers across the globe, sharing with one another the list of domain names (spestechnologies.com, for example) and what IP addresses they correspond to.

Since multiple services (the visitors, couriers, etc) such as email, chat, video messaging and others are also dependent on a domain name, there are different types of records (doorways to rooms of the household) to accommodate these scenarios.

Creating a new home address

New domain registrations are automatically added to one of these root-level DNS servers and then replicated to all the others globally. Additional records (internal doors) can be created at any time and it can take up to 72 hours to replicate the changes all around the globe. However, a simple mistake such as a typo can result in a website going offline, email getting cut off for the entire business or other bizarre and intermittent issues.

Keep the flow of kitten pictures going but do be careful. Stray kitties, cute as they may be, are generally bad for the environment if gone unchecked. They can carry diseases, tear up the insulation and duct work under your house and will claw your eyes out if you try to touch them. Similarly, one must use extreme caution when making any changes to DNS records. As always, please don’t hesitate to contact us if you have any questions.

As another relatively quiet hurricane season comes to a close, some are breathing a sigh of relief. Maybe not so much here in South Carolina where we have had devastating losses because of Hurricane Matthew. Two major disasters in as many years is a lot to go up against. Add in the wildfires in the Upstate region and our little state has taken quite the beating recently. Unfortunately this does not mean that we’re due for a break. In fact, it’s a great time to ensure that we’re ready for the next disaster that will hit us, whatever and whenever that may be.